Adhesive products



Oct. 31, 1961 3. WHEELER Ill ADHESIVE PRODUCTS 2 Sheets-Sheet 1 FiledAug. 19, 1960 FIG. 2

FIG.

w m m mm m M w IE A H a W H H S L DZ Oct. 31, 1961 5. WHEELER m ADHESIVEPRODUCTS 2 Sheets-Sheet 2 Filed Aug. 19, 1960 FIG.

FIG.

INVENTOR. SETH WH EELER, IE, BY 7' ATTORNEYS FIG. 6

linited States Pater 3,036,793 ADL ESIVE PRODUCTS Seth Wheeler IH,Painesville, Ohio, assigncr to Avery Adhesive Froducts, inc, Monroria,Califl, a corporation of Caiiicrnia Filed Aug. 19, B69, Ser. No. 59,6372 Claims. (*Cl. 154-535) This invention relates to web combinations forthe manufacture of adhesive articles, such as labels, stickers, tapesand the like. More particularly the invention relates to webcombinations for the manufacture of articles of the above type whichhave backings for protecting and for accomplishing containment of theadhesive coating which is to be employed in mounting the article in itsend use.

Fibrous materials such as paper, clot-h and-the like have been commonlyemployed as backings to protect and contain the adhesive coating oradhesive surface for roducts such as labels, stickers, tapes and thelike. One of the requisites for such backings is that they remainsecurely in protecting and containing relationship with the adhesivesurface during manufacture and distribution of the articles while alsobeing capable of easy and convenient removal by the end user when thearticle is to be mounted or afiixed on the surface with which it is tobe associated in its ultimate end use.

Of importance to an aspect of the present invention is an appreciationthat partially degraded zones in a fibrous backing web cansatisfactorily accomplish adhesive containment and remain capable oftransmitting relatively high transverse tensile stresses under nobending when such zones are degraded to an extent that (1) allows theweb material within the zones to remain capable of transmitting therelatively low transverse tensile stresses necessarily encounteredduring separation from a backing web while under a degree of bendingnecessarily encountered during such separation but (2) results in readyrupture of the web material within the zones when the web is bent to adegree greater than that necessarily encountered during such separation.Such relatively high tensile strength under no bending may besu-fliciently higher than the relatively low tensile stress encounteredduring separation of the backing webs to permit the pulling forces forcausing separation of the backing web across a long zone to betransmitted across a short zone of only a fraction of the length of thelong zone.

it is particularly advantageous to provide stock for the manufacture ofself-adhesive articles, such as labels, stickers, tapes and the like,with web combinations which will provide for easy removal of theprotective backing by the end user without any substantial departurefrom the conventional production processes and apparatus of themanufacture of such labels, stickers, tapes and the like.

It is even more particularly advantageous to provide for manufacture ofeven the sheet stock (from which the label, sticker or tape manufacturerwill make the end use article) in such a manner that the feature of easyremoval of the protective backing may be accomplished on-line in suchconventional web combining and web processing production runs withoutsubstantial production cost increases.

The present invention makes it possible to realize these advantageousresults in such a manner as to inherently result in the provision on theend use article of latent starting tabs of small, conveniently graspablewidth.

Other advantages and features of the invention will become apparent fromthe following detailed description and drawings illustrating an exampleof the invention.

FIGURE 1 is va view of a length of stock material exemplifying theinvention.

FIGURE 2 is a greatly enlarged detail view of the portion of the rightband edge of the stock material shown in FIGURE 1.

FIGURE 3 is a schematic sectional view taken from line 33 in FIGURE 2,assuming that the structure shown in FlGURE 2 has been severed alongline 30 and the thickness of the webs being exaggerated for clarity.

FIGURE 4 is a view similar to FIGURE 3 showing the illustrated webcombination in a bent position.

FIGURE 5 is a view similar to FIGURES 3 and 4 showing the removal of aportion of the protective backmg.

FIGURES 6 and 7 are diagrammatic representations of one stage in themanufacture of products contemplated by the invention.

A fibrous backing sheet it} is provided which is in appositerelationship with the adhesive coating 11 on a base web 12, the web 10constituting means for protetcting and for accomplishing containment ofthe adesive coating 11.

Along the length of the backing sheet 10 are a succession of narrowcmbn'ttled zones 14 which are integrally included in the backing sheet'10 and thus integrally form a part of the means for protecting and foraccomplishing containment of the adhesive coating 11.

As most clearly shown in FIGURE 1, the zones 14 (which for clarity areindicated in FIGURE 1 merely as lines) extend across the backing sheet10 from side to' side thereof and in skewed relationship to both thelengthwise and w-idthwise directions of the web combination.

The backing material 10 may be any suitable conventional backingmaterial such as paper, cloth, or the like. The narrow zones 14 areproduced by subjecting the backing 10 to treatment with an agent whichcauses the treated portions of the backing to become brittle. Theembrittled zones may be produced by applying heat, a flame, a chemicalsubstance such as sulfuric acid or ultraviolet radiation, or the like topartially degrade or decompose the treated portions of the backing.

By way of example, if the embrittled zones are pro duced by applying afiuid such as for example sulfuric acid, the embrit-tled zones may becontinuously produced by an operation which is essentially a printingoperation where a roll with helical printing ridges formed thereon iscontacted with the backing web 10 before or after its combination withthe Web 12 to thereby print the series of narrow embrittled zones 14 inan endless manner and in an on-line relationship with the remainder ofthe web combining and processing steps in the manufacture of the stockshown in FIGURE 1. This is indicated diagrammatically in FIGURES 6 and 7where the backing web 10 is shown moving in the direction of the arrowshown in FIGURE 6 past the printing roll or plate roll 21 having aplurality of raised helical ridges 22. The crowns of the ridges 22 arecoated with the printing liquid, for example sulfuric acid, by a formroll 23 which in turn is supplied by a fountain roll 24 which is incontact with a bath of the printing liquid 25.

The web 11) may be supported during the printing operation by a backingroll 27. V

The partial degradation contemplated by the invention may beaccomplished for example by providing a relatively dilute bath of theliquid 25 and then progressively adding the active agent therein, as forexample sulfuric acid, until on a trial basis it is determined that acondition has been reached where the backing web material 10 willrupture at the printed zones when bent to a degree greater than thatnecessarily encountered during transmitting such relativelyhighrstresses.

Accordingly, it will be clear that the. web combiner who manufacturesthe stock shown in FIGURE 1 may include therewith by low-cost, on-linemethods, the succession of narrow embrittled zones 14 within'the backing:web 10. The combined stock comprising the adhesivecoated web 12 and thebacking web 19 may then be supplied to manufacturers of labels,stickers, tapes and the like as for example by being provided in rollsof considerable length. Such rolls are arranged so that the curvature ofthe rolled stock does not exceed the curvature which'will result inrupturing of the embrittled zones 14.

.:When the stock is die cut or otherwise severed by the manufacturer oflabels, stickers, tapes or the like, the skewed orientation of theembrittled zones 14 will result in the provision of latent starting tabsin the end product of small conveniently graspable width which ma be Yvery conveniently manipulated. Assume now that the combined stock inFIGURE 1 is severed by the end user along the equally spaced lines 28,29 and 3G and an indefinitely long succession of additional lines ofseverance to thereby form a plurality of rectangular web portions 3134and a long succession of additional rectangular web portions. Startingtabs will thereby be formed at both the upper right hand corner and'thelower left hand corner of such rectangular web portion, references todirection being with respect to the product as viewed in FIGURE 1. Thus,for example, the line of severance 30 will define a small triangularcorner portion 35 in the rectangular web portion 34. Such triangularportion 35 is seen on an enlarged scale in FIG- URES 2 and 3. Thebacking sheet 10 may be easily and simply removed from the label,sticker, tape or the like represented by the base Web 12 in FIGURE 3 byfirst bending the composite product at or near one of the embrittledzones 14 to such a degree that, as shown in FIGURE 4, the embrittledzone 14 is caused to rupture dividing the backing 10 into two parts. Thedivided backing is then removed by grasping the edge of the backing atthe point of rupture and peeling the major part of the backing from theadhesive surface as shown in FIGURE 5. Other embrittled zones such asthe particular zone 14 shown in FIGURE 5 Will remain intact as thebacking is peeled from the adhesive sufiace because the embrittled zones14 are self-sustaining under the tensile stress and limited bendingrequired to peel the backirn sheet from the adhesive. As previouslymentioned, they are also self-sustaining under no bending, even whensubjected to higher tensile stresses. In these connections it will beunderstood that as the stripping operation progresses from the upperright hand corner of the particular rectangular web portion 34,progressively greater pulling force is required to further continue thestripping operation because the line of cleavage between the webs 16 and12 becomes progressively longer, at least during the initial portion ofthe stripping operation. As cleavage proceeds past each succeeding zone14, the tension per unit area through each succeeding Zone does notincrease significantly for the reason that the lengths of the succeedingzones 14 increase in proportion to the increasing length of the line ofcleavage. However the shorter zones 14 through which cleavage firstoccurs must carry progressively higher tensile stresses as the line of iby the user.

cleavage becomes progressively longer and the pulling force becomesprogressively greater, but such relatively high tensile stresses occursubstantially in the complete absence of bending and the fibrous webmaterial within the zones 14 can carry such relatively high tensileloads in these conditions.

The above description relates in detail to the removal of the backingweb 10 of the rectangular web portion 34.

It will be understood that the same considerations generally apply inthe case of the other rectangular web portions 31-33 and in fact in thecase of any rectangularly oriented labels, stickers, tapes or the like,which may for example be formed by die cutting in a conventional manner.For example, if three rectangular labels are die cut across the width ofthe web combination shown in FIGURE 1, each of them would be providedwith a corner starting tab and the backing web would be separabletherefrom in the same general manner as described above.

It is to be noted that the above description does not include theremoval of the small triangular portion 35. This may be accomplished bygrasping the edge of the triangular portion at the line of rupture andflicking oil the small triangle.

It is to be particularly noted that the boundaries of die-cut objects,or the lines of severance, such as the lines 28-31), need not be in anyparticular register with the pattern of zones 14. Thus, as illustratedin FIGURE 1, the lines of severance are out of register with the zones14 so that the line 29 forms a small corner triangle 36 which it will beassumed is too small to be readily grasped In such an event, the usertreats the nextsmallest cornentriangle as the starting tab, suchnextsmallest corner triangle including the triangle 36 and beingindicated by the reference numeral 37. The major portion of the backingsheet 10 is then removed by the end user as above described and thetriangle 37 (including the portion 36) may be flicked off as a unit inthe same manner as the triangle 35.

in still another case, a line of severance may exactly intersect one ofthe zones 14 as indicated at the line of severance 28. In this case thetriangle 38 will obviously be larger than the triangle 35 and will be ofsulficient size to form, at its hypotenuse, a conveniently usablestarting tab. p

The invention is not restricted to the slavish imitation of each andevery one of the details described above which have been set forthmerely by way of example with the intent of most clearly setting forththe teaching of the invention. Obviously specific structural details maybe changed or eliminated without departing from the invention.

What is claimed is:

1. An article of manufacture comprising a web combination extending in along direction and including a base web having an adhesive coating onone surface and a protective flexible fibrous backing sheet in appositerelationship with said adhesive coating and constituting means forprotecting and for accomplishing containment of said adhesive coating,said backing sheet having along its length a succession of narrowembrittled zones which are integrally included in said backing sheet tothereby integrally form part of said means for protecting and foraccomplishing containment of said adhesive coating, said zones extendingacross said backing sheet from side to side thereof and in skewedrelation to both the lengthwise and widthwise directions of saidwebcombination.

2. An article of manufacture comprising a web combination extending in along direction and including a base web having an adhesive coating onone surface and a protective flexible fibrous backing sheet positionedin protectingand containing relationship against said adhesive coatingand constituting means for protecting and for accomplishing containmentof said adhesive coating, said backing sheet having along its length asuccession 01': narrow embrittled zones which are integrally included insaid backing sheet to thereby integrally form part of said means forprotecting and for accomplishing containment of said adhesive coating,said zones extending across said backing sheet from side to side thereofand 5 of registration between said embrittled zones and said articles.

References Cited in the file of this patent articles cut from said webcombination independently 10 ,73

UNITED STATES PATENTS Martin Nov. 5, 1901 Salfisberg Feb. 2, 1937Salfisberg Dec. 28, 1937 Flood Dec. 1, 1942 Brady June 22, 1954

1. AN ARTICLE OF MANUFACTURE COMPRISING A WEB COMBINATION EXTENDING IN ALONG DIRECTION AND INCLUDING A BASE WEB HAVING AN ADHESIVE COATING ONONE SURFACE AND A PROTECTIVE FLEXIBLE FIBROUS BACKING SHEET IN OPPOSITERELATIONSHIP WITH SAID ADHESIVE COATING AND CONSTITUTING MEANS FORPROTECTING AND FOR ACCOMPLISHING CONTAINMENT OF SAID ADHESIVE COATING,SAID BACKING SHEET HAVING ALONG ITS LENGTH A SUCCESSION OF NARROWEMBRITTLED ZONES WHICH ARE INTEGRALLY INCLUDED IN SAID BACKING SHEET TOTHEREBY INTEGRALLY FORM PART OF SAID MEANS FOR PROTECTING AND FORACCOMPLISHING CONTAINMENT OF SAID ADHESIVE COATING, SAID ZONES EXTENDINGACROSS SAID BACKING SHEET FROM SIDE TO SIDE THEREOF AND IN SKEWEDRELATION TO BOTH THE LENGTHWISE AND WIDTHWISE DIRECTIONS OF SAID WEBCOMBINATION.